Electrical contact device



Feb. 21, GAVA ET 2,498,410

ELECTRICAL CONTACT DEVICE Filed Oct. 9, 1945 iatentecl Feb. 21, 1950Andre Gavallet, Par'isjFrance I Application October 9, 1945, Serial No.621,293 I In France August 1, 1945 1 The present invention has for itsobject a new contact device for a lamp or other electrical equipment onone or several lighting leads and for all types of electrical contactconnections.

The bayonet lamp holder of the present construction offers poorconditions of contact due to the very weak contact surface of the wireends on the lamp. The contact between the springpiston and the lamp onone side and between the pistons, lodgings and springs on the otherside, having a, relative movement to each other are generally defective.The present construction gives also difficulties in mounting anddismounting with a possibility of a short-circuit chiefly due todefective condition of the fastening of the outcoming wires. It consistsin arranging in the holder a cylindrical block, displaceable along itsaxis and susceptible to making with the elements of the lamp, or similardevice, a contact, by means of a pressure plug with or without anelastic element in between. The pressure plug serves also otherpurposes; it insures the rigidity of the wires on the block due to itspressure.

In order to give an example and. to facilitate the understanding of thisdescription a drawing Fig. 3 is a schematic view from the front side ofone of the modifications of a piston.

Fig. 4 is a construction which permits an arrangement of a lamp shade.

Figs. 5, 6 and '7 are various construction forms.

Fig. 8 is a longitudinal section of a box for the junction of thecables.

Figs. 1 and 2 are related to a bayonet lamp holder, a device, which isthe subject of this invention, consisting of an exterior holder I' withan interior screw thread 2 in the inside of which is placed acylindrical block 8, which is displaceable in the said holder in themanner of a piston in a cylinder. The guidance of the block in thecylinder is carried out by means of projecting edges or ribs l and. ISon the block 8 coacting with grooves 3 and 4 on the interior side of theholder. The holder possesses cutouts 5 for the bayonets visible on thesubmitted drawing.

The block 8 admits entries such as grooves and holes, which serves forfixing the wires to the block. The two wires 9 and I0, which conduct thecurrent, penetrate free from the top down through the plug 6 they gothen into the two deep notches II, l2, of the piston which are 4 Claims.(Cl. 173-328) located on opposite sides are bent on the bottom part ofthe piston at 13 and I4, and the wires are in this area stripped oftheir insulation if they have'to be clamped here to a branching device.The wires gothen up through the channels I! and 18 in the'neighborhoodof the grooves and are bent again and redescend then in the side groovesI9, 20 of the piston. I

It should be noticedfthat the device is described for only twoconducting wires, but itis evident that the invention applies also toany number of conductors or wires under the condition that'the wires'canbe conveniently pulled through the piston. g I

Looking on the plug 6 of the holder it can be seenthat the conductingwires are subjected to two bendings and are therefore absolutelyimmobile when subjected to the action of the pressure. The pressure iscreated between the screwplug and the piston and between the piston andthe clamps of the branching arrangement maintained in thebayon'etdevice. I

It can be also seen thatby removing the 'plug from the holder, thepiston can be'raised free disconnecting the contact and permitting thedisassembling of the bayonet system or of all other connecting means. IIt can be equally remarked that in orderto realize some number ofcontacts derived from the conductors it was found advantageous toreplace the channels l'i, l8 of the piston by deep grooves whichdisposition avoids cutting the wires.

In Figure 3 is seen a modification of a blockpiston for two conductorsin which said conductors are maintained in the deep grooves 2|, 22, 23and 24.

In the modification shown in Figure 4, the contacts are arranged in thesame manner, but the pressure-plug 6, carries here a cap 1 which permitsto arranging of a lamp shade of big dimen- 310118.

The modification Fig. 5 carries a holder 3! with an exterior thread 32.The pressure piece 36 has here a form of a bell with an interior screwthread. By screwing this bell over the threads 32 by means of the part33 a pressure is applied to the block-piston 38. A lamp shade orsomething similar can be arranged by means of an exterior ring 31.

In the modification shown in the Fig. 6, the pressure-piece 43 of asuitable shape which in the shown example is conical, presses the block48 in the holder M by means of an exterior cap of the same diameter,

"therein,

46 having a slanted portion 45 for coacting with v the conical piece 43.

In the modification shown in Fig. 7 the holder consists of two piecesand 52. The piece 5| has a ring shaped rim 53 and the piece 52 a screwthread over which is screwed a ring-piece 54, the latter permits thecontrol of the pressure by pulling together the pieces 5| and 52. Thepiece 5| with itsshoulder' 55 is playing the same role as the cup33 ofthe Figure 5; it exercises a pres sure on the block 58.

A junction box for at least one conductor shown in Figure 8. Itsconstruction is based on the same principle as of the holder of the Fig.1; but it carries a block for each end or group'of ends of conductors.The exterior holder 6! receives here two plugs 66 andfi'l and each ofthem is resting on the block-pistons 68 and 69 which are pressedtogether by means of saidgplugs and ensure the direct electrical contactof the naked portions of the conductors which are inserted Having nowdescribed and ascertained the nature of my invention and the manner inwhich the same is to be performed, I declare that what I claim is: v v I1.-An electrical contact device comprising an external holdenmeans onsaid holder for securing an electrical device, a cylindrical slidableblock piston having flat end surfaces in said holder, said blockpistonhavinga plurality of openings therein for :passage of wirestherethrough, a pressure plug adjustably mounted on said holder, meansfor adjusting said..pressure plug, and wires passing through saidopenings in said block piston having a'portion thereofvextending alongeach said' fiat-end surface, said portions of said wires on one saidflat end surface being free of insulation for providing adequateelectric contact, said pressure plug adjustably pressing against saidslidable block piston for urging the same into engagement with anelectrical device and for securing said wires against displacement.

2. An electrical contact device comprising-an external holder having athreaded portion, means on said holder for securing ,anelectrical devicetherein, a cylindrical slidable block piston having vflat end surfacesin said holder, said block-piston '4 having a plurality of openingstherein for passage of wires therethrough, a threaded pressure plugadjustably mounted on said holder and coacting with said threadedportion, and wires inserted through said openings in said block pistonhaving a portion thereof extending along each said flat end surface,said portions of said wires on one said fiat end surface being free ofinsulation for providingadequate electric contact, said pressure ,plugadjustably pressing. against said slidable block piston for urging thesame into engagement with an electrical device and for securing saidWires against displacement.

3. An electrical contact device as claimed in claim 1, said openings insaid block piston being parallel to the axis thereof and so arrangedthat said wires inserted therethrough will follow a tortuous'path andhave a double bend, said portion extending along one said fiat endsurface serving as a contact and that portion on the other said endbeingsecuredby said pressure REFERENCES CITED The following references are ofrecord inrthe The of this patent:

UNITED STATES PATENTS Number Name Date L 2,110,508 Klopfer Man-8,1938

, FQREIGNPATENTS' 1 f .N-umber Country D e 111,447 Great Britain of 1917205,209 Great Britain of ;1923 588,403 France of 1925 1 Australia of1932

